Jasper S. Halekas - University of Iowa

My long form CV.
Also see my Google Scholar Page.


My latest paper utilizes ARTEMIS measurements of plasma frequency oscillations to probe the tenuous lunar ionosphere present when the Moon traverses the Earth's magnetospheric tail.


My recent paper utilizes MAVEN observations to reveal the global structure of the Martian magnetosphere under different solar wind conditions, including the primary force terms in the momentum equation. This paper received an Editor's Highlight in Eos.


My recent paper describes unique new observations from MAVEN which show that the hydrogen exosphere of Mars varies by an order of magnitude over the Martian year, with a peak near southern summer solstice.


This recent paper describes the inflight performance and first results from the Solar Wind Ion Analyzer, the instrument I lead for the MAVEN mission. Some of the new results include a global overview of magnetospheric structure and variabiliy, and some of the first measurements of Alfven waves and foreshock dynamics at Mars.


This paper describes a new method for analyzing pickup ion observations, which allows us to constrain atmospheric composition by timing the delay in the response of pickup ions to the passage of magnetic field discontinuities. Our results suggest a surprisingly large contribution from heavy exospheric species.


This paper in GRL discusses MAVEN observations of bulk escape of plasma from Mars in the form of coherent "clouds" that are stripped away from Mars by the solar wind.


I was third author of and led the charged particle investigation described in one of our four initial Science papers from MAVEN, which presented the exciting results from our subsolar deep dip campaign, where we measured the structure and dynamics of a region of the upper atmosphere never previously visited.


I was heavily involved in one of our four initial Science papers from MAVEN, describing the impact of a significant space weather event on the magnetosphere of Mars.


Our MAVEN first results include a paper that I led describing the deposition of solar wind hydrogen in the Martian atmosphere. This hydrogen undergoes a charge exchange with the corona, penetrates the magnetosphere as an energetic neutral atom, and then undergoes electron stripping or electron attachment to convert to H+ or H- that we can observe with MAVEN.


Our MAVEN first results include a paper that I led describing the first observation of time-dispersed ion signatures at Mars. These appear to be created by pickup of heavy Martian ions in time variable electric fields.


A paper describing LADEE NMS ion-mode observations of newly born ions from the tenuous lunar exosphere. These new data show that the lunar exosphere contains an unexpected population of carbon-bearing particles, apparently originating from either solar wind or micrometeorite bombardment.


A paper from 2014 describing the latest ARTEMIS observations of small-scale collisionless shocks generated by solar wind reflection from lunar magnetic fields. This paper provides the strongest evidence to date that shocks actually do form at the Moon, and suggests that these may be some of the smallest collisionless shocks in the solar system, at least in terms of plasma scales.